Letalis noster

When frisk found her she was injured her wing was broken so frisk offered her a dead monster which healed her wing from there frisk and letalis had an unbroken bond and now frisk rides letalis and helps frisk in hunting and scouting the land letalis can breathe fire due to two tubes in her mouth one to make the gas the other to egnite it letalis appears to be some sought of big cat  the only thing that has ridden letalis is frisk and only frisk if anything tried they would get chucked off.